1991367504 has 240 divisors, whose sum is σ = 6954554880. Its totient is φ = 538876800.

The previous prime is 1991367481. The next prime is 1991367527. The reversal of 1991367504 is 4057631991.

1991367504 is a `hidden beast` number, since 1 + 9 + 9 + 136 + 7 + 504 = 666.

It is an interprime number because it is at equal distance from previous prime (1991367481) and next prime (1991367527).

It is a self number, because there is not a number n which added to its sum of digits gives 1991367504.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 515179 + ... + 519029.

It is an arithmetic number, because the mean of its divisors is an integer number (28977312).

Almost surely, 2^1991367504 is an apocalyptic number.

1991367504 is a gapful number since it is divisible by the number (14) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 1991367504, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (3477277440).

1991367504 is an abundant number, since it is smaller than the sum of its proper divisors (4963187376).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

1991367504 is a wasteful number, since it uses less digits than its factorization.

1991367504 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3900 (or 3882 counting only the distinct ones).

The product of its (nonzero) digits is 204120, while the sum is 45.

The square root of 1991367504 is about 44624.7409404245. The cubic root of 1991367504 is about 1258.1057250163.

The spelling of 1991367504 in words is "one billion, nine hundred ninety-one million, three hundred sixty-seven thousand, five hundred four".